A research group used a scientific analysis to determine whether a group of serial killers thought to be psychopaths actually ...

However, serial killers typically commit the murders over an extended period and allow time to elapse between each. Mass murderers, by contrast, commit all their murders in a brief, one-time event.

READ ON THE FOX NEWS APP In contrast, a spree murder happens when a person kills two or more ... or behavioral characteristic ...

Here's a look at five serial killers from Connecticut. Also referred to as the "Sick Ripper," William Devin Howell killed ...